Power hammer



A. F/. CRESIEN July 12, 1938.

POWER HAMMER Filed Aug. 15, 1936 5 Sheets-Sheet 1 Invenlorflibrff'fasz'em,

Jul 12, 1938. A. F. CRESIEN 2,123,563

POWER HAMMER Filed Aug. 15, 1936 3 Sheets-Sheet 2 EIEIZE/M Inventor ByWan/5M i g Attorneys July 12, 1938. A. F. CRESIEN 2,123,563

POWER HAMMER Filed Aug. 15, 1936 s'sheets-sheet 5 ZZWw/EM. 5

A ito rneys Patented July 12, 1938 UNITED STATES PATENT OFFICE 3 Claims.

This invention relates to power hammers and the objects of the inventionare to provide a gasoline driven hammer which may be used for drill ing,demolition work or other purposes, to pro- Vide a hammer which isportable, and also to provide a hammer having safety features associatedtherewith to the end that the hammer will cease operating when pressureis released on the handle.

Briefly, the invention consists in the provision of a gasoline driven,air cooled, two cycle hammer which will be found to possess numerous andadvantageous features over the types of power hammers now generallyemployed.

The invention together with its objects and advantages will be bestunderstood from a study of the following description taken in connectionwith the accompanying drawings wherein:

Figure l is an elevational view of the improved power hammer.

Figure 2 is a longitudinal sectional View through the hammer.

Figure 3 is a horizontal sectional view through a latch mechanismforming part of the invention.

Figure 4 is a fragmentary longitudinal sec tional View through a rodassembly forming part of the invention.

Figure 5 is a fragmentary detail sectional view showing the manner ofconnecting the handle with a casting forming part of the invention.

Figure 6 is an enlarged detail sectional view through a carburetor inletassembly forming part of the invention.

Figure 7 is a top plan view of an air breather, and

Figure 8 is a side elevational view of the air breather with certainparts broken away and shown in section.

Referring to the drawings by reference numerals it will be seen that inthe preferred embodiment thereof the improved power hammer comprises asubstantially hollow handle 5, which includes a hollow cross member 6having depend- 45 ing therefrom parallel extensions 1. The handle 5forms a container for fuel, in the present instance gasolene and to thatend at one end of the grip 5, the handle 5 is provided with a fillingneck It).

Further the invention comprises a casting 9 that has extended fromdiametrically opposite sides thereof lugs 8, which as best shown inFigure 5 are provided with a socket which receives the tapered solidends of the handle extensions 55 l. Screws or similar fastening elements4 serve to positively secure said ends of the handle extensions withinthe sockets of the lugs 8.

The block 9 has formed integrally therewith a cylinder i5 in whichoperates a piston M.

The piston i4 is guided in its movements through the medium of guiderods ll suitably anchored within a bored portion of the block 9 as shownin Figure 2. Also within the lower end of the bored portion of the block9 is an impact assembly I 3 for operating the tool l2 which is connectedwith the impact assembly it through the medium of a chuck or othersuitable coupling H.

The bored portion of the block 9 below the piston M constitutes acarburetor having an inlet 32.

Suitably associated with the inlet 32 of the block 9 is a casting whichincludes an air intake valve 35 fitted within the intake 32 and con'trolled by a valve disk 33 having a stem operating in a suitable guidestructure 34 and with which is associated a spring 36 that normallyretains the valve 33 seated at the inner end of the intake 3!. The guide34 is provided with openings 35 through which air from the atmosphereenters the neck 3| to pass from the neck 3| into the carburetor portionof the block 9 below the piston I4.

The lower ends of the handle extension 1 are provided with ports 2| thatregister with ports 2la. provided in the lugs 8. Suitably cored withinthe blocks 9 is a passage 2lb that connects the passages 21a with apassage 22 (see Figure 6) that opens into a fuel reservoir 23.

The fuel in the reservoir seeks a suitable level, and the level of fuelin the reservoir 23 may be ascertained by looking through a sight window25 with which the reservoir 23 is suitably equipped. In the top thereofthe reservoir 23 is provided with a suitable plug 24. At the bottomthereof, the reservoir 23 is provided with a collector cup 26 and a tubeEl arranged centrally of the cup 26 and extending through the bottom ofthe reservoir chamber 23 into an integral valve casing 28. Collector cup26 and tube 2i are so designed as to prevent vapor lock and also theformation of bubbles that would interrupt the gasoline supply under highvibration.

Leading from one end of the valve casing 28 through the peripheral wallof the intake neck 3! is a. fuel passage 30 which is also controlled bythe valve 33 as shown in Figure 6.

From the above it will be seen that on each upward stroke of piston 94,fuel from the handle 5 flows through the ports 2|, 21a, Zlb, 22 into thereservoir 23.

From the reservoir 23, fuel passes through the tube 21 into the valve28, and from the valve 28 through the passage 30 and from the jet 30,the fuel passes into the intake 32 of the carburetor portion of castingof block 9. At the same time, valve 33 being open air from theatmosphere is drawn into the carburetor portion of the block 9 through abreather 54 hereinafter more fully referred to and past the valve 33 tomix with the fuel admitted into the carburetor in the manner justexplained.

Formed in the block 9 and wall of cylinder I is a passage 3 which at oneend opens into the carburetor portion of the block 9 and at its otherend opens as at 2 into the cylinder I5 above the piston I4 when thelatter is in its lowest position. A plug for the port 2 as indicated bythe reference numeral 31 is provided as shown in Figure 2.

Thus it will be seen that as the piston I4 moves downwardly the fuelmixture below the piston within the block 9 is compressed and forcedthrough the passage 3 and port 2 into the cylinder I5 above the pistonI4. On the compression stroke of the piston I4 the fuel admitted intothe cylinder I5 will be compressed and at the end of this compressionstroke the fuel compressed by the upward movement of the piston will beexploded through the medium of the igniting as sembly 28 which may be ofany suitable design. Obviously the force of the exploding gases will acton the piston I4 to move the same downward. Thus the cycle of operationis continuously repeated so that the piston I4 in its reciprocatoryaction acts on the impact assembly I3 in a manner to operate the toolI2.

The breather assembly 54 includes a union 54a that connects the pipewith a nipple 542) that is received within a recess 3Ib provided in thecasting assembly of Figure 6 at the side of the guide 34 opposite to thevalve 33. Pipe 54 is provided with airports 55 through which the airpasses from the atmosphere through the breather, the passages 35, andpass the valve 33, when the latter is in open position to mix with thefuel entering the carburetor portion of the block 9 below the piston I4.

As shown in Fig. 2 the make and break ignitor which may be of anysuitable construction and design, and forms no part of the presentinvention is preferably of the compression responsive type and istherefore under the control of piston l4, and is suitably mounted on ahead I9 provided for the cylinder I5.

The head I9 is suitably bored to provide a guide for actuator rod 49that moves vertically through the head I9 and has an inner end adaptedto engage the head of the piston I4 for initiating downward movement ofthe piston as will hereinafter be more fully explained.

Slidably associated with the rod is a tubular rod 4| which at its lowerend is provided with a pair of spaced collars between which are pivotedlatch dogs 41 between one end of which is a spring 48 that normallyurges the free ends of the dogs 41 inwardly towards one another.

Rods 40 and 4| are normally urged towards one another through the mediumof a spring 42 which at one end is anchored within the rod 4|, and atits opposite end is secured to the upper end of the rod 49 as clearlyshown in Figure 4.

Also at its upper end the rod 40 is provided at opposite sides thereofwith grooves or slots 53 with which the latch element 41 engage when therod 4| is moved upwardly relative to the rod 40, as and for a purposehereinafter more fully explained.

At its upper end the rod 4| is bifurcated to receive an intermediateportion of a bracket 43 the opposite ends of which are suitably securedto a handle member I pivoted at one end to a clamp 45 secured about anend portion of the grip 6 of handle 5.

Also and as clearly shown in Figures 1 and 4, suitably provided in thebifurcated end of the rod 4| is a roller 46 which engages theintermediate portion of the bracket 43.

From the above it will be seen that to initiate operation of the hammer,handle I is swung upwardly for pulling the rod 4| upwardly relative tothe rod 40. As the rod 4| moves upwardly, latch members 41 are broughtopposite the grooves and under action of spring 48 move inwardly intoengagement with the grooves 50 thus locking the rods 40 and 4| together.When a this locking of these rods 49 and 4| is effected, handle I isthen moved downwardly. As handle I moves downwardly rod 49 at its innerend engages the piston I4 at the head of the latter and forces saidpiston downwardly of the block 9 against the action of spring I8. Asbefore mentioned as the piston I4 moves downwardly the fuel mixturebelow the piston is forced through the passage 3 and the port 2 into thecylinder I5 above the piston I4.

Rising from the cap I9 in the path of the levers 41 is the suitablyshaped lug 5|. It will thus be seen that as rods 40 and 4| movedownwardly for moving the piston I4 downwardly as and for the purposejust mentioned, the latch members 41 will ultimately engage with the lug5| spreading these latch members 41 apart and out of engagement with therod 4|, thus releasing the rod. Upon release of the rod 40, the springI8 will act on the piston I4 to move the same, forcibly, upwardly tocompress the fuel admitted into the cylinder I5 above the piston I4. Aspiston I4 moves upwardly on its compression stroke sufiicient pressurewill be developed for setting in operation the make and break device 20to ignite the compressed fuel above the piston l4. Ob-

. viously under the force of the explosion, piston I4 will then movedownwardly on its power stroke against the action of spring I8, and thiscycle of operation is repeated for the continuous operation of thehammer.

It will be understood that the igniting device 20 may be arranged in asuitable battery circuit and for controlling this circuit there isprovided a switch consisting of a contact 53 suitably mounted on andinsulated from the grip B of handle 5 and a contact 52 suitably mountedon and insulated from the handle I and bracket 43. Thus as the handle Imoves downwardly for moving the piston I4 downwardly in the manner aboveexplained, the contact 52 will engage contact 53 thus completing thecircuit through the ignition device 20 for firing the charge compressedby the upward movement of the piston I4.

In connection with the above it will be understood that during thedesired operation of the hammer, handle I is depressed sufficiently tomaintain contacts 52 and 53 engaged. Thus it will be seen that when itis desired to stop the operation of the hammer, pressure is releasedfrom the handle I and under influence of the spring contact 52 handle Iwill move slightly upwardly to separate the contacts 52 and 53.

For scavenging the cylinder I5 the latter is provided with an exhaustport 39 which opens to the atmosphere. Thus it will be seen that aspiston l4 moves downwardly in response to the explosive action of thegases, port 39 as well as port 2 will be uncovered. Thus the burnt gaseswill escape through the port 39 and the fuel mixture from below thepiston M will be admitted into the cylinder i5 above the piston M.

For controlling the supply of fuel through the jets 30 into thecarburetor chamber of the block 9, there is accommodated within thevalve casing 28 a needle valve 29 arranged to control the jet 30 asshown in Figure 6.

Since the operation of the invention was described as the description ofthe details of the invention progressed, it is thought unnecessary torepeat in detail the operation of the device, and that the same will beclear from the foregoing.

Having thus described the invention what is claimed as new is:

1. In a device of the character described, the combination with acylinder having a floating piston reciprocable therein, an impactassembly in the lower end of said cylinder, and a spring acting uponsaid piston and in opposition to the movement thereof toward said impactassembly; means for initiating movement of the piston against the actionof the spring and including a head for said cylinder having a boretherethrough, an actuator rod slidable through the bore in said head andhaving an inner end adapted to engage the piston for moving the latterdownwardly, a tubular rod slidably mounted on said actuator rod, andinterengaging means on the actuator rod and on said tubular rod forreleasably connecting said rods together when the tubular rod is movedin one direction relative to the actuator rod whereby upon reversemovement of said tubular rod said actuator rod is caused to moveinwardly of the cylinder to engage the piston for moving the lattertoward said impact assembly in opposition to said spring, and means onthe upper end of the cylinder for releasing the rod at the completion ofthe movement of the piston toward said impact assembly, whereby saidactuator rod is free to telescope inwardly of the tubular rod incidentalto the return movement of the piston.

2. In a device of the character described, the

combination with a cylinder having a piston reciprocating therein; ofmeans for initiating movement of said piston including an actuator rodmovable through the upper end of the cylinder and inwardly of the latterto engage the piston to move the latter in one direction, a tubular rodslidable on said actuator rod, said actuator rod being provided adjacentone end thereof with grooves, spring pivoted dogs on said tubular rodengageable with said grooves to releasably secure said rods againstrelative movement when the tubular rod is moved outwardly of saidactuator rod, whereby both of said rods are caused to move inwardly toengage the actuator rod with said piston, and a lug mounted on the upperend of the cylinder in the path of said dogs to release the rods at thecompletion of the movement of the piston toward said impact assembly,whereby said actuator rod is free to telescope inwardly of the tubularrod upon return movement of the piston.

3. In a device of the character described and in combination with acylinder having a floating piston reciprocable therein, of means forinitiating movement of the piston including a head for said cylinder andhaving a. bore therethrough, an actuator rod slidable through the borein said head and having an inner end adapted to engage the piston tomove the latter in one direction, a tubular rod slidably mounted on saidactuator rod, interengaging means on the actuator rod and said tubularrod for releasably connecting said rods together when the tubular rod ismoved in one direction relative to the actuator rod whereby upon reversemovement of said tubular rod said actuator rod is caused to moveinwardly of the cylinder to engage said piston for moving the latter insaid one direction, a handle member pivotally mounted at the headequipped end of said cylinder, a bracket member secured at itsrespective opposite ends to said handle and having its intermediateportion spaced from said handle, and roller means on one end of saidtubular rod and engaging the intermediate portion of said bracketwhereby swinging movement of the handle member is transmitted to saidtubular rod.

ALBERT F. CRESIEN.

